Method and apparatus for coating fibers



Jan. 3, 1956 w. w. DRUMMOND ET AL 2,728,972

METHOD AND APPARATUS FOR COATING FIBERS 2 Sheets-Sheet 1 Filed April 10 1951 INVENTORS Mann WEMDBLL DHUMMUND 531mm .5. .5 aux.

BY M TTORNEYS.

Jan. 3, 1956 w. w. DRUMMOND ET AL 2,723,972

METHOD AND APPARATUS FOR COATING FIBERS 2 Sheets-Sheet 2 Filed April 10. 1951 INVENTORS WARREN Wzzmz'zz Z712 uummn ATTORNEY 5 United States Patentf) METHOD AND APPARATUS FORCOATING FIBERS Warren Wendell Drummond and George E. Smock, Newark, Ohio, assignors to' Owens-Corning Fiberglas Corporation, Toledo, Ohio, acorporation of Ohio Application April 10, 1951, SerialNo. 220,284 11 Claims. (Cl. 28'e-=-1)' This invention relates to a method and apparatus for coating elongated bodies and moreparticularly to a method and applicator means for transferring fiowable coating material to moving bodies such as filaments,.fibers or linear groups of fibers.

In the formation and processing, of fibers or filaments formed from various" fiber-forming materials such as glass, it has been conventional practice to apply a lubricant, sizing or other liquid to the" fibers to minimize fiber inte'rabrasion and hence reduce the liability of fiber breakage as well as to enhance the integrity of a strand or linear group formation of the fibers; One of. the conventional methods heretofore employed in applying a lubricant or size to mineral fibers has included the use of a cylindrical roll of comparatively small diameter engaged by the fibers in tangential relation thereto forlimited contact or engagement therewith to effect-- a transfer of a film of the lubricant or size to the fibers.

In the manufacture of glass fibers where streams of glass are attenuated to fine fiber form, the rollemplbyed for applying lubricant or size has" been formed with a graphite fiber engaging. surface by reason of itsv inherent antifriction characteristics. In continuous commercial operations the fibers travel at many times the speed of the roll which results in wearing ruts or grooves in the comparatively soft graphite and within a short time the roll must be resurfaced or reconditioned and the ultimate life of a roll of this character is relatively short;

Several difficulties have been encountered in applying a film or coating to the fibers in the above mentioned manner. The coating material is conveyed to the applicator roll through the use of a pad of felted material disposed in wiping contact with the roll surface, the pad being impregnated with the coating material. Opjeration of this arrangement for a; period of time results in excessive wear of the pad interfering with the efficient transfer of the coating material to the roll and aifording little control of the application of the material to the fibers. Furthermore, sizing materials of a waxy character when used tend to congeal on the pad and interrupt the coating application, a condition fostering breakage of the filaments or fibers resulting in fly formation. Such conditions when encountered necessitate temporary discontinuance of the fiber forming operation to collect and dispose of the accumulated fly and recondition or cleanse the pad of congealed or accumulated coating material.

The invention embraces a method of impartingaj coating of lubricant or size to mineral fibers wherein an'a'dequate' control over the coating application operation may be had and wherein the fibers are brought into contact with a film of coating material in a manner facilitating a more thorough application and uniform distribution of the coating on the fibers than has heretofore beenpossible through the utilization of prior methods.

The present invention contemplates the provision of a coating applying apparatus particularly usable for coating mineral fibers such as glass wherein a continuously movingapplicator element directly acquires .a filmzcf 2,728,972 Patented vJan. 3, 1956 2- coating material by immersion and transfers the same to the fibers through wiping contact of the fibers with the applicator element.

An object of the invention is the provision of a method of applying a film or coating to fibers wherein the angle of engagement of the fibers with an applying means is of a character utilizing the surface tension and adhesion of the coating material to increase the effective zone of engagement of the fibers with the coating material where: by an improved distribution of the coating material. on the fibers is facilitated.

An object of the invention is the provision of a cylindrical rotatable applicator element or medium provided with an elastomer surface having the. characteristics of being readily wetted by the fiber coating mate: rial whereby the coating. may be transferred to fibers engaging the elastomer surface with a minimum of friction and hence avoiding wear of the material transferring surface.

Another object of the invention embraces the provision of an applicator means provided with a removable sleeve or sheath of elastomer material such as synthetic rubber or the like having the characteristics of being readily wetted by the coating material, the sleeve being of a substantial diameter and disposed in a manner whereby the elongated bodies or fibers to be coated are caused to contact the coating material through a comparatively large area or greater linear distance for a longer period of time whereby a more effective application of the coating'is had with a consequent increase in the strand integrity of the fibers in group formation whereby. the. character of the fibrous strand is improved and brashiness minimized.

Another object of the invention is' the provision of a coating applying apparatus especially adaptable for coating fine fibers of mineral material wherein. an appli cator roll acquires a film of coating material by immer sion or dipping in the coating material whereby the same is transferred to the fibers by surface contact therewith, the apparatus being provided with an arrangement for continuously circulating coating material adjacent'the applicator roll to assure a constant and uniform film being maintained on the roll for transfer to the fibers.

Still another object of the invention is the provision or a fiber coating applicator arranged to continuously acquire a film of liquid coating material directly by surface contact or immersion from a quantity of the material in a receptacle, the apparatus including means for continuously moving the applicator at a uniform speed whereby a substantially uniform coating of the material is imparted to the fibers. 2

Still another object of the invention is the provision of an applicator means formed of material which is readily wetted by the coating and which is of elastomcr or semiresilient character engaging the fibers with a minimum of friction with consequent longevity of the applicator means.

Another object of the invention resides in an apparatus including an applicator roll of a comparatively large diameter which is continuously rotated for transferring a coating or sizing to continuously moving fibers, the arrangement including a rotatable means for gathering the fibers into a linear group or strand which is concomitantly rotated with the applicator roll through the medium of a single operating. means or motor.

Further objects and advantages are within the scope of this invention such as relate to the arrangement, operation and function of the related elements of the structure, to various details of construction and to combinationsof parts, elements per se, and to; economics of manufacture consideration of the specification and drawing of a form of the invention, which may be preferred, in which:

Figure l is a semidiagrammatic view illustrating a form of our invention utilized for establishing a coating or sizing on mineral fibers which are formed through attenuation of streams of fiber forming material;

Figure 2 is a front elevational view of an embodiment of the invention;

Figure 3 is an end view of the construction shown in Figure 2; and

Figure 4 is an enlarged fragmentary view illustrating the method of effecting a transfer of a film of coating material to fibers.

While an arrangement of the apparatus is illustrated as employed for coating, sizing or lubricating fine glass fibers attenuated from molten streams of glass, it is to be understood that the utilization of the invention is contemplated in any processing operation wherein it is desirable to impart a coating, sizing or lubricant to various types of fibers including those formed from fusible rock, slag or fiber-forming resins.

Referring to the drawings in detail and first with respect to Figure 1, there is illustrated a forehearth or tank it? beneath which is disposed a feeder ll formed with a plurality of orifices or openings through which flow streams of fiber-forming material contained in the forehearth. The streams are attenuated to fibers 14 by any suitable attenuating instrumentality as by winding the fibers upon a spindle or drum 15, or by engaging the fibers with attenuating rolls traveling at comparatively high speeds for drawing the streams to fine fibers. The linear groups or strands of fibers formed by this method are adaptable for various uses and especially in the textile industry.

It is highly desirable that the fibers be adequately coated or provided with a thin film of lubricant, size or other coating material to augment the strength of the strand of fibers through minimizing interabrasion of the fibers and hence reducing liability of breakage of the fibers and avoiding brashiness.

As particularly shown in Figures 2 and 3, the illustrated form of apparatus for, carrying out the method of fiber coating includes a frame plate upon which is supported a receptacle 22 preferably formed of sheet metal, the receptacle 22 being adapted to contain a quantity of lubricant, sizing, or other fiber coating material 23.

The receptacle 22 is provided with an inlet 25 for admitting liquid coating material from a supply contained in a reservoir 26. The inlet 25 may be connected with a source of supply by means of a tube 27, a valve 28 being intercalated in the tube or feed line 27 for regulating the flow of coating material into the receptacle 22. The valve 28 may also be utilized to interrupt the flow of coating material when the apparatus is not in use.

The receptacle 22 is also provided with an outlet tube or exit duct 29, the outlet thereof being disposed at a vertical distance with respect to the base of the receptacle for determining the level of coating material to be maintained in the receptacle. A liquid circulating means or pump 30 may be utilized to feed the coating material into the receptacle 22 and to establish continuous circulation of the material if desired. The coating material may however be fed to the receptacle by elevating the supply reservoir 26 above the receptacle 22. With gravity feed the outlet tube 29 conveys the excess coating liquid to a sump from which it may thereafter be subsequently pumped or otherwise returned to the reservoir.

The apparatus is inclusive of a coating transferring medium or means for imparting or applying a coating to the fibers 14 formed from the streams of material flowing from the feeder 11. The coating applying means or applicator means is inclusive of a supporting shaft 31 upon which are secured disks or spiders 32 supporting a cylindrical sleeve or tube 34 preferably formed of lightweight material such as phenolformaldehyde condensation product known as Bakelite or other suitable material which will not be affected by the coating material to be deposited upon the fibers. The tube 34 is adapted to snugly receive and support a cylindrical element or sleeve 3 formed of synthetic rubber or other suitable material which is preferably of semiresilient or elastomer character. It has been found that synthetic rubbers of the butadiene acrylonitrile or chloroprene types marketed under the trade names of Hycar and Neopreme provide an effective coating transfer medium. The synthetic rubber sleeve is of a character which when wetted within a coating material sets up infinitesimally small friction between the elastomer surface of the sleeve element and the fibers whereby wear of the sleeve by reason of its engagement with the fibers is reduced to a minimum.

As particularly shown in Figure 3, the sleeve 36 is journaled in the receptacle 22 so that the lowermost zone of the sleeve is immersed in the liquid coating material so that the sleeve during rotation is actually continuously dipped into the coating and therefore continuously acquires a film of the material for transfer to the fibers.

The sleeve 36 and its supporting arrangement are adapted to be rotated at a comparatively low peripheral speed compared with the linear speed of the fibers. The means illustrated for rotating the sleeve includes a motor 40 preferably of the electrically energizable type, the motor shaft 42 being provided with a worm gear (not shown) adapted for enmeshment with a worm wheel (not shown) contained within a gear housing 44 and mounted upon a shaft 45. Secured upon the shaft 45 is a spur gear 47 which meshes with a spur gear 48 of larger diameter, the latter being secured upon the shaft 31 supporting the sleeve 36. Thus the sleeve 36 is operated at a comparatively slow speed through the reduction gearing afforded by the worm and Worm wheel drive (not shown) and the differential in the size of the spur gears 47 and 48.

The sleeve 36 is of comparatively large diameter of five inches or more whereby a substantial area of contact is established with the moving fibers by reason of the angular direction of travel of the fibers into engagement with the sleeve 36 with respect to the direction of travel of the fibers moving away from the sleeve such that the fibers are in an arcuate contact with the periphery of the sleeve and the liquid film thereon for a substantial distance.

While the mathematical distance of arcuate linear engagement of the fibers with the peripheral surface of the sleeve 36 is determined by the diameter of the sleeve and the relative angles of travel of the fibers engaging and moving away from the sleeve measured on the arcuate or cylindrical periphery of the sleeve, the actual zone or area of contact of the fibers with the liquid film on the sleeve is much greater than such distance in the arrangement of the present invention. Figure 4 is illustrative of the above mentioned condition. In this figure the fibers 14 travel downwardly into contact with the sleeve 36 at an angle A with respect to a vertical plane tangent to the periphery of the sleeve 36. The fibers move away from the sleeve substantially in the aforementioned plane of tangency and hence the angular change in direction of travel of the fibers is angle A. The actual contact of the moving fibers with the surface of the sleeve 36 is the arcuate peripheral distance defined by the angle B which is equal to angle A.

Due to the characteristics of adhesion and surface tension of the liquid coating whereby the coating readily Wets the fibers 14 and the elastomer surface of the sleeve 36, the actual fiber coating zone is of much greater area than actual contact of the fibers with the sleeve. The effective fiber coating zone is therefore existent between the points indicated at 37 and 38 being the respective meniscus surfaces defining the length of the column of liquid coating material between the sleeve surface and the fibers. vThus by utilizing an applicator or sleeve of comparatively large diameter, agreatly increased efiective coating area or zone is provided so that a uniform distribution of coating is established on the fibers without any loss of coating material;

With this arrangement a comparatively largefiber coating area or zone is provided as compared with the actual contact of the fibers with the sleeve, a condition facilitating the establishment of a substantially uniform coating on the fibers. The rate of linear travel of the attenuated fibers is upwards of ten thousand feet or more per minute and transfer of the coating through the increased area of contact of the fibers with the film on the sleeve is measurably improved over prior fiber coating methods.

This increased area of coating contact provides for a better and more thorough application and disposition of the coating material upon the fibers so that when gathered into strand or linear group formation there is provided a high degree of strand integrity.

The apparatus may be provided with a means for gathering or compacting the fibers into a strand or linear group. As illustrated in Figures 2 and 3, the fiber gathering means may be in the form of a circumferentially grooved member or spool having a fiber engaging surface of graphite, the spool being suitably journaled upon a member 52 which is riveted or otherwise secured to a depending arm 53. The depending arm 53 has a horizontal portion 54 which is slotted to accommodate a winged bolt 55 which is threaded into an opening formed in the frame plate 20. The slot in the portion 54 provides a means for adjusting the fiber gathering member 50 with respect to the periphery of the sleeve 36 to attain the most effective fiber gathering position for the spool 56.

It is desirable that the fiber gathering spool 50 be rotated in order to minimize Wear upon this element. As illustrated the spool 50-may' be connected by means of a flexible shaft contained in a sheath 61 with a shaft 63 journaled in a suitable member 65 mounted upon the frame plate 20. Secured upon the shaft 63 is a spur gear 66 also in enmeshment with the larger spur gear 48. Thus a drive connection is established between the motor 40 and the gathering spool 50 through the gear reducing worm and worm Wheel mechanism connected to the motor shaft, the gear 66 and flexible shaft 60. The speed of rotation of the sleeve 36 and the fiber gathering spool 50 is preferably between forty and fifty revolutions per minute which has been found to be a satisfactory operating speed, but other speeds may be utilized to advantage dependent upon the sizes or character of fibers or filaments or other elongated bodies being coated.

The receptacle 22 and coating transfer means are suitably enclosed within a shield 70 preferably of inverted U-shaped configuration in cross-section as illustrated in Figure 3, the rear wall being hinged as at 72 to the rear upper portion of the wall of the receptacle 22. The forward portion of the shield 70 is provided with a slot or recess 73 to permit the fibers to engage the periphery of the sleeve 36 at the coating zone. The front wall of the receptacle 22 is recessed as at 76 to accommodate the sleeve 36.

The apparatus hereinbefore described is preferably mounted upon a relatively movable support so that the apparatus may be swung away from the path of travel of the fibers or bodies to be coated. To accomplish this purpose, the apparatus may be supported upon an arm 80 which is pivotally connected to a stationary support 82 by means of a pivot shaft or bolt 83. The arm 80 may be formed at its outermost end with a handle portion 85 for manipulating the apparatus about the axis of the shaft 83. The plate 20 carrying the coating apparatus may be secured to the arm 80 by means of U-shaped bolts or clamps 81. The stationary support 82 may be provided with an adjustable abutment or stop 84 adapted to engage the arm softer indexing the latter to a ositron: of: use, via, the position illustrated in- Figures" 1 to 3 inclusive.-

fects substantial savings of the coating material for the reas'o'n thatmaterial on the sleeve that is not transferred to the fibers is returned to the receptacle for further use so that no-loss of material is encountered in this coat-ing arrangement. As indicated in Figure 4, the fibers are in engagement with the periphery of the sleeve through a considerabledistance and by reason of the angular change in direction of travel of the fibers and the comparatively large diameter of the sleeve 36 coupled with the charac teristics of surface tension and adhesion of the coating,- the fibers" are in: contact with the film of coating material on the sleeve for a distance not over an area considerably greater than the actual surface engagement of the fibers with thesleeve. By reason of the greater length of contact of the fibers with the coating material or size on the applicator, the fibers are exposed to the coating or size for a longer period of time. This condition facilitates adequate wetting or coating. of the fibers with thinner layers of sizing material on the sleeve.- The arrangement of the present invention renders it unnecessary to flood or overload the' fibers to secure wetting out and transfer of the desired amount of size as has heretofore been a requisite practice in prior methods ofcoating. Because of 'the rapidity of oscillation of the strand or linear group of fibers below the gathering roll, the excess size on the fibers applied by a saturated pad or a graphite roll ofcomparatively small diameter was loosened and thrown ofi of the fibers. The method of size application of this invention avoids overcoating of the fibers and hence loss of sizing by discerption from the fibers is eliminated. Thus the apparatus of the present invention is eflicient and effective in carrying out the method of transferringv the lubricant or other coating material to the fibers re sulting in a very thorough and uniform disposition of the coating on the fibers.

It is apparent that, within the scope of the invention, modifications and different arrangements may be made other than are herein disclosed, and the present disclosure is illustrative merely, the invention comprehending all variations thereof.

What we claim is:

1. Apparatus for coating moving fibers with a liquid including in combination, an element having a cyliudrical surface of synthetic rubber; means for continuously rotating the element in the same general direction as the moving fibers and at a speed less than that of the fibers; a receptacle adapted to contain the liquid coating material; said element being disposed whereby the synthetic rubber surface during rotation of the element acquires'a film of the liquid by engagement with the liquid in the receptacle; means for guiding the fibers in individually spaced relation and directing each of the fibers into engagement with the synthetic rubber surface whereby the fibers follow the curvature of the surface for a substantial distance to effect a transfer of a coating of liquid from the film on the synthetic rubber surface to the fibers, and means for maintaining a predetermined level of the liquid coating material in the receptacle.

2. Apparatus for coating continuous mineral fibers moving at a high linear speed with a liquid material including, in combination, a cylindrical element; a receptacle adapted to contain liquid coating material; means for maintaining the liquid material at a predetermined level in the receptacle; said element being journally supported whereby the cylindrical surface thereof acquires a film of the liquid material by contact with the material in the receptacle; means for rotating the cylindrical element in the general direction of movement of the fibers and at a'peripheral speed less than the linear rate of movement of the fibers; the diameter of the element and the diretcion of travel of the fibers being of a character whereby the fibers engage the film on the cylindrical surface for a substantial area to effectively transfer liquid material from the surface to the fibers to establish a uniform coating thereon; a rotatable member adapted to engage and collect the coated fibers into a strand formation, and means for rotating the member concomitantly with rotation of the cylindrical element.

3. Apparatus for coating continuous mineral fibers moving at a high linear speed with a liquid material including, in combination, a cylindrical element having an elastomer peripheral surface; a receptacle adapted to contain liquid coatng material; means for maintaining the liquid material at a predetermined level in the receptacle; said element being journally supported whereby the clastomer surface acquires a film of the liquid material by contact with the material in the receptacle; means for rotating the cylindrical element in the general direction of movement of the fibers and at a peripheral speed substantially less than the linear rate of travel of the fibers; the diameter of the element and the direction of travel of the fibers being of a character whereby the fibers contact the film on the elastomer surface for a substantial area to effectively transfer liquid material from the elastomer surface to the fibers to establish a uniform coating thereon; a rotatable member adapted to collect the coated fibers into a linear group formation; means for rotating the member concomitantly with the rotation of the cylindrical element, and means for circulating liquid material through said receptacle from a supply to replenish material transferred therefrom to the fibers.

4. Apparatus for coating continuous mineral fibers moving at a high linear speed with a liquid material, in combination, a coating-applying means including a receptacle adapted to contain liquid coating material; a cylindrical element having a peripheral surface of yieldable material; said element being mounted for rotation and partially immersed in the material in the receptacle whereby the surface of yieldable material acquires a film of the coating material; means connecting a source of supply of the material with said receptacle including a fluid pump for delivering material from the supply to the receptacle; means for maintaining the liquid material at a predetermined level in the receptacle; means for directing individually spaced fibers to be coated into engagement with the yieldable surface of the element; a journally supported, grooved fiber-gathering wheel having a fiber engaging surface formed of graphite spaced from the yieldable fibercoating surface; means for simultaneously rotating the cylindrical element and the grooved fiber-gathering wheel in the general direction of movement of the fibers and at a speed less than that of the fibers, the diameter of the cylindrical element and the direction of travel of the fibers into engagement with and away from the yieldable surface being of a character whereby the fibers contact the film of coating material on the surface for a substantial linear distance to efiectively transfer coating material from the surface to the individual fibers to establish a uniform coating thereon, and a support for the coatingapplying means including a pivotally mounted arm adapted to be swung from fiber-coating position to an ineffective position.

5. Apparatus for coating continuous mineral fibers moving at a high linear speed with a liquid material, in combination, a coating-applying means including a receptacle adapted to contain liquid coating material; a cylindrical element having a peripheral sleeve of synthetic rubber; said element being rotatably mounted and disposed so as to be partially immersed in the material in the receptacle; a source of supply of coating material; means connecting the supply with the receptacle including a fluid pump for delivering coating material from the supply to the receptacle and circulating the material in the receptacle; means for maintaining the material at a predetermined level in the receptacle; means for directing fibers to be coated into engagement with the peripheral surface of the sleeve in spaced relation; a grooved fibergathering wheel journally supported at a zone spaced from thefiber-coating sleeve; means for simultaneously rotating the cylindrical element and the grooved fiber-gathering wheel, the diameter of the sleeve and the direction of travel of the fibers into engagement with and away from the surface of the sleeve being of a character whereby the fibers contact the film of coating material on the sleeve for a substantial linear distance to effectively transfer liquid material from the sleeve to the individually spaced fibers to establish a uniform coating thereon; a support for the coating-applying means, and a shield disposed above the receptacle to exclude foreign matter therefrom.

6. A method of establishing a coating on each of a plurality of continuous fibers formed of heat-softenable material including concomitantly advancing the fibers while they are in transversely spaced apart relation at a comparatively high speed in the general direction of their length, causing the advancing fibers to engage a surface adapted to be wetted by the coating material, continuously moving the surface in the general direction of travel of the fibers at a speed less than that of the fibers and into contact with a supply of coating material whereby a film of the coating material is continuously transferred by the surface to the fibers through engagement of each of the fibers With the film-bearing surface, continuously circulating the coating material adjacent the surface, and changing the linear direction of travel of the fibers moving away from the surface whereby the fibers are in contact through adhesion with the film on the surface throughout a substantial linear distance to establish a uniform coating on each of the fibers.

7. A method of establishing a coating on continuous glass fibers including moving a plurality of individual fibers in spaced apart relation at a comparatively high speed in a rectilinear path in wiping engagement with a surface, continuously moving the surface in a curvilinear path in the general direction of travel of the fibers at a speed less than that of the fibers through a supply of coating material whereby a film of the coating material is transferred by the surface to the fibers through Wiping engagement of each of the fibers with the film-bearing surface, continuously circulating the coating material adjacent to and in contact with the surface, and changing the rectilinear direction of travel of the fibers as they move away from engagement with the surface whereby the fibers are in contact through adhesion with the film on the surface throughout a substantial linear area to establish a uniform coating on each of the fibers.

8. Apparatus for applying a liquid to spaced apart fibers moving in a rectilinear direction at a high rate of speed including, in combination, a rotatable element provided with an elastomer surface, means for rotating the element whereby the periphery moves in the general direction of travel of the fibers, a receptacle adapted to contain liquid to be applied to the fibers, means for maintaining a predetermined level of the liquid in the receptacle, said element being disposed to contact the liquid in the receptacle whereby the elastomer surface acquires a film of the liquid during rotation of the element, means spaced from the element for gathering the fibers into a strand as they move out of engagement with the elastomer surface, the wiping contact of the fibers with the film on said surface effecting a transfer of a coating of the liquid on each individual fiber, said fiber gathering means controlling movement of the fibers in an arcuate path coincident with the elastomer surface for a limited peripheral distance of said surface.

9. Apparatus for applying a liquid to spaced apart fibers moving in a rectilinear direction at a high rate of speed including, in combination, a rotatable element provided with a peripheral surface adapted to be wetted by the liquid, means for continuously rotating the element whereby the peripheral surface moves in the general direction of travel of the fibers, a receptacle adapted to contain the liquid to be applied to the fibers, means for maintaining a predetermined level of the liquid in the receptacle, said element being disposed to contact the liquid in the receptacle whereby the peripheral surface thereof acquires a film of the liquid during rotation of the element, means spaced from the element for gathering the fibers into a linear group as they move out of engagement With the peripheral surface of said element, the wiping contact of the fibers with the film on said surface efiecting a transfer of a coating of the liquid onto each individual fiber, said fiber gathering means controlling movement of the fibers in an arcuate path coincident with the peripheral surface of said element for a limited peripheral distance of said surface.

10. Apparatus for applying a coating material in a flowable state to spaced apart fibers formed by attenuating streams of heat-softened fiber forming material, in combination, rotatable means for gathering the spaced fibers into a strand, means for applying a coating of the material to the fibers in advance of the fiber gathering means including a rotatable applicator provided with a cylindrically shaped fiber engaging surface adapted to be Wetted by the fiber coating material, a receptacle arranged adjacent the applicator and adapted to contain a supply of fiber coating material, means for predetermining the level of the coating material in the receptacle, said applicator being positioned whereby the cylindrically shaped surface thereof is partially immersed in the coating material in the receptacle and acquires a film of the material during rotation of the applicator, and means for rotating the applicator and the fiber gathering means in the same general direction as the fibers and at linear peripheral speeds less than the speed of travel of the fibers.

11. Apparatus for coating spaced apart glass fibers formed by attenuating streams of glass moving at comparatively high linear speed to form continuous fibers, in combination, means including a rotatable member for collecting the fibers into a linear group, means for applying a liquid coating to the fibers while said fibers are in spaced relation in advance of the fiber collecting means including a rotatable applicator provided with a peripheral surface adapted to be Wetted by the liquid coating material, a receptacle arranged adjacent the applicator and adapted to contain liquid coating material, means for maintaining a predetermined level of coating material in the receptacle, said applicator being positioned whereby the peripheral surface thereof is partially immersed in the coating material and acquires a film thereof during rotation of the applicator, means for circulating the liquid coating material from a supply through the receptacle, means for continuously rotating the applicator and the fiber collecting means in the same general direction as that of the fibers and at a linear speed less than the speed of the fibers, a relatively movable cover for the receptacle, and a relatively movable support for the applicator adapted to shift the applicator out of engagement with the fibers.

References Cited in the file of this patent UNITED STATES PATENTS 1,505,432 Ruff Aug. 19, 1924 1,929,192 Taylor Oct. 3, 1933 2,016,085 Fawkes Oct. 1, 1935 2,199,228 Obenshain Apr. 30, 1940 2,272,588 Simison Feb. 10, 1942 2,287,426 Hageman June 23, 1942 2,392,805 Biefeld Jan. 15, 1946 2,491,889 Bennett et al Dec. 20, 1949 FOREIGN PATENTS 707,140 Germany June 14, 1941 942,914 France Sept. 27, 1948 

1. APPARATUS FOR COATING MOVING FIBERS WITH A LIQUID INCLUDING IN COMBINATION, AN ELEMENT HAVING A CYLINDRICAL SURFACE OF SYNTHETIC RUBBER; MEANS FOR CONTINUOUSLY ROTATING THE ELEMENT IN THE SAME GENERAL DIRECTION AS THE MOVING FIBERS AND AT A SPEED LESS THAN THAT OF THE FIBERS; A RECEPTACLE ADAPTED TO CONTAIN THE LIQUID COATING MATERIAL; SAID ELEMENT BEING DISPOSED WHEREBY THE SYNTHETIC RUBBER SURFACE DURING ROTATION OF THE ELEMENT ACQUIRES A FILM OF THE LIQUID BY ENGAGEMENT WITH THE LIQUID IN THE RECEPTACLE; MEANS FOR GUIDING THE FIBERS IN INDIVIDUALLY SPACED RELATION FNAD DIRECTING EACH OF THE FIBERS INTO ENGAGEMENT WITH THE SYNTHETIC RUBBER SURFACE WHEREBY THE FIBERS FOLLOW THE CURVATURE OF THE SURFACE FOR A SUB- 